SAD: Is seasonal affective disorder a bipolar variant?
Patients with seasonal bipolarity require different treatment from those with unipolar SAD
Physiopathologic findings and clinical management for SAD vs BD
| SAD | BD | |
|---|---|---|
| Differences | May be unipolar or bipolar Defined by seasonality Light therapy and antidepressants indicated | Increased risk of psychosis and psychiatric hospitalization Most BD is not seasonal Mood stabilizers indicated Risk of switching states with light therapy and antidepressants |
| Similarities | Atypical depressive symptom presentation Highly recurrent Predictable season of recurrence allows proactive treatment Assess for mania and hypomania in both disorders Light therapy requires clinical supervision Psychotherapy may be beneficial | |
| BD: bipolar disorder; SAD: seasonal affective disorder | ||
Table 3
Recommended treatment for bipolar disorder with seasonal pattern
| Treatment | Recommendation |
|---|---|
| Mood-stabilizing medications | Maintain year-round, especially in patients with BP I |
| Antidepressants | Consider those with efficacy in unipolar SAD or nonseasonal bipolar depression |
| Light therapy | Initiate for 5 to 10 min/day for bipolar depressive episodes in patients receiving mood stabilizers or atypical antipsychotics; slowly increase duration while monitoring mood, sleep, and side effects to manage risk of hypomanic or manic switch |
| Psychotherapy | Consider CBT or interpersonal and social rhythm therapy to help manage symptoms and reduce episode recurrence |
| BP I: bipolar disorder type I; CBT: cognitive-behavioral therapy; SAD: seasonal affective disorder | |
CASE CONCLUSION: Ongoing treatment required
After several months of light therapy, Ms. S begins to feel better and reports having more energy. We taper her light therapy to 10 minutes daily in the morning from late February until 1 week after daylight saving time begins in mid-March. Weekly phone calls during this transition screen for signs of hypomania or mania. Lamotrigine is effective in preventing switches in spring.
Future plans include monitoring for hypomania through summer and possibly reinitiating light therapy in fall or winter. Because approximately one-half of individuals who undergo CBT for SAD do not experience another episode the winter after treatment, light therapy will be initiated only if depressive symptoms emerge. A booster session is scheduled with Ms. S’s CBT therapist in early fall to reinforce relapse prevention skills.
Antidepressant therapy will be recommended if full treatment response is not maintained with light therapy and continued use of CBT skills for SAD. During sessions, we emphasize compliance with lamotrigine. On several occasions Ms. S questions the need for ongoing therapy, but with education about the potential effects of mania she agrees to continue treatment as indicated.
Seasonality screening tools
- Seasonal Pattern module of the Structured Clinical Interview for DSM Disorders (SCID). www.scid4.org/faq/clinician_version.html.
- Hypomania Interview Guide for Seasonal Affective Disorder (HIGH-SAD). www.chronotherapeutics.org/Tools_ENG.html.
- National Institutes of Health Life Chart Method. www.bipolarnews.org/Clinician%20Life%20Charting.htm.
- Structured Interview Guide for the Hamilton Depression Rating Scale—Seasonal Affective Disorder Version (SIGH-SAD). www.chronotherapeutics.org/Tools_ENG.html.
Bipolarity screening tools
- Bipolar Spectrum Diagnostic Scale. Click here to download.
- Bipolarity Index. https://psycheducation.org/depression/STEPBipolarityIndex.htm.
Light therapy
- Wirz-Justice A, Benedetti F, Terman M. Chronotherapeutics for affective disorders: a clinician’s manual for light and wake therapy. Basel, Switzerland: S. Karger AG; 2009.
- Wirz-Justice A, Benedetti F, Berger M, et al. Chronotherapeutics (light and wake therapy) in affective disorders. Psychol Med. 2005;35(7):939-944.
Psychotherapy
- Rohan KJ. Coping with the seasons: a cognitive-behavioral approach to seasonal affective disorder (therapist guide). New York, NY: Oxford University Press; 2008.
- Frank E. Treating bipolar disorder: a clinician’s guide to interpersonal and social rhythm therapy. New York, NY: Guilford Press, Inc.; 2005.
Drug brand names
- Aripiprazole • Abilify
- Bupropion • Wellbutrin XL
- Carbamazepine • Tegretol
- Citalopram • Celexa
- Fluoxetine • Prozac
- Lamotrigine • Lamictal
- Lithium • Eskalith, Lithobid
- Quetiapine • Seroquel
- Sertraline • Zoloft
- Thioridazine • Mellaril
- Valproate • Depakote
Disclosures
Drs. Roecklein and Rohan report no financial relationship with any company whose products are mentioned in this article or with manufacturers of competing products.
Dr. Postolache received an investigator-initiated award from The LiteBook Company (Vancouver, Canada) via the Society for Light Treatment and Biological Rhythms, as well as research support from Apollo Health (Salt Lake City, UT).
